Business decision tool
Customer Concentration Risk Calculator
Summarise revenue concentration across the five largest customers.
Inputs and results stay in this browser. Currency symbols are illustrative; use any consistent currency.
Understand Customer concentration
One idea, three depths
Choose how deeply to explain Customer concentration
Customer concentration: Summarise revenue concentration across the five largest customers.
Age 5Explain it to a 5-year-oldStart with a picture
Imagine using Customer concentration to answer this question: summarise revenue concentration across the five largest customers? Enter Customer 1 revenue share, Customer 2 revenue share, Customer 3 revenue share, and 2 other inputs; the calculator shows Top-five revenue concentration. Try changing one number and watch what happens to Top-five revenue concentration. The answer tells you Top-five revenue concentration.
Age 15Explain it to a 15-year-oldConnect it to the formula
Higher concentration can increase dependence on a small number of customers. The five-customer HHI is partial when other customers are omitted. The rule is Top-five concentration = share₁ + share₂ + share₃ + share₄ + share₅; HHI = Σ shareᵢ². Its input values are Customer 1 revenue share (%), Customer 2 revenue share (%), Customer 3 revenue share (%), Customer 4 revenue share (%), Customer 5 revenue share (%), and the main result is Top-five revenue concentration. Try changing one number and watch what happens to Top-five revenue concentration.
CollegeExplain it at college levelState the model precisely
This tool models one operating decision from explicitly supplied company assumptions. The implemented relation is Top-five concentration = share₁ + share₂ + share₃ + share₄ + share₅; HHI = Σ shareᵢ², evaluated from Customer 1 revenue share (%), Customer 2 revenue share (%), Customer 3 revenue share (%), Customer 4 revenue share (%), Customer 5 revenue share (%) to produce Top-five revenue concentration. Higher concentration can increase dependence on a small number of customers. The five-customer HHI is partial when other customers are omitted. The model omits unentered taxes, cash timing, legal constraints and market uncertainty. Compare the output with company records and a downside scenario before committing resources.
The decision this tool supports
Summarise revenue concentration across the five largest customers.
Why the business model works
Higher concentration can increase dependence on a small number of customers. The five-customer HHI is partial when other customers are omitted.
Inputs and operating assumptions
This model uses Customer 1 revenue share (at least 0), Customer 2 revenue share (at least 0), Customer 3 revenue share (at least 0), Customer 4 revenue share (at least 0), Customer 5 revenue share (at least 0). Keep currencies, accounting treatment and time periods consistent with one another.
The formula
Top-five concentration = share₁ + share₂ + share₃ + share₄ + share₅; HHI = Σ shareᵢ²
What the calculator produces
The primary output is Top-five revenue concentration; it also exposes Five-customer HHI contribution. Change one assumption at a time so the comparison remains explainable.
Before using the result in a decision
This compact model cannot capture every tax, accounting, legal, market or operational condition. Compare the output with current company records, cash timing and the downside scenario before committing resources.
Supporting sourcesAcademic referencesPrimary standards, textbooks and complete citations
Standards, reading and academic references
Use the calculator as the worked interaction, then consult the primary standards and academic textbooks listed below. MW SysArc links to the original sources; the explanation on this page is original and does not reproduce them.
Introduction to Business 2e
Read the free OpenStax business textbookCite this book
- APA 7
- Gitman, L. J., McDaniel, C., Shah, A., Reece, M., Koffel, L., Talsma, B., & Hyatt, J. C. (2026). Introduction to business 2e. OpenStax. https://openstax.org/books/introduction-business-2e/pages/1-introduction
- MLA 9
- Gitman, Lawrence J., et al. Introduction to Business 2e. OpenStax, 2026, https://openstax.org/books/introduction-business-2e/pages/1-introduction.
- Chicago author-date
- Gitman, Lawrence J., Carl McDaniel, Amit Shah, Monique Reece, Linda Koffel, Bethann Talsma, and James C. Hyatt. 2026. Introduction to Business 2e. Houston, TX: OpenStax. https://openstax.org/books/introduction-business-2e/pages/1-introduction.
OpenStax entries are free to read online. Follow the licence shown on each linked source before redistributing or adapting its content.
Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS
These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.
APA 7
MW SysArc. (2026, July 21). Customer Concentration Risk Calculator. MW SysArc Tools. https://business.mwsysarc.com/customer-concentration-risk
MLA 9
MW SysArc. “Customer Concentration Risk Calculator.” MW SysArc Tools, 21 July 2026, https://business.mwsysarc.com/customer-concentration-risk. Accessed 31 Aug. 2026.
Chicago 17
MW SysArc. “Customer Concentration Risk Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed August 31, 2026. https://business.mwsysarc.com/customer-concentration-risk.
Harvard
MW SysArc (2026) ‘Customer Concentration Risk Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://business.mwsysarc.com/customer-concentration-risk (Accessed: 31 August 2026).
BibTeX and RIS records
BibTeX
@misc{mwsysarc_customer_concentration_2026,
author = {{MW SysArc}},
title = {Customer Concentration Risk Calculator},
howpublished = {MW SysArc Tools},
year = {2026},
url = {https://business.mwsysarc.com/customer-concentration-risk},
note = {Published July 21, 2026; accessed August 31, 2026}
}RIS
TY - ELEC
AU - MW SysArc
TI - Customer Concentration Risk Calculator
T2 - MW SysArc Tools
PY - 2026
DA - 2026-07-21
Y2 - 2026-08-31
UR - https://business.mwsysarc.com/customer-concentration-risk
N1 - Published July 21, 2026
ER -Clear answers
Frequently asked questions
What does the Customer concentration do?
Summarise revenue concentration across the five largest customers.
How does the Customer concentration work?
The calculator applies Top-five concentration = share₁ + share₂ + share₃ + share₄ + share₅; HHI = Σ shareᵢ². Higher concentration can increase dependence on a small number of customers. The five-customer HHI is partial when other customers are omitted.
What can I learn from the Customer concentration?
It connects company inputs to a transparent business result. Change one value at a time to compare operating scenarios.
Does MW SysArc receive or store what I enter?
No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.
How should I use the result?
Use the result as a practical reference. Review the inputs, assumptions and stated limitations before relying on it.
Last reviewed . Calculations tested .